• 4-Line to 1-Line Data Selectors/Multiplexers
That Can Select 1 of 16 Data Inputs Typical
Boolean Function Generators
Data Source Selectors
• Cascadable to n-Bits
• 3-State Bus Driver Outputs
• ’AS850A Offers Clocked Selects; ’AS851B
Offers Enable-Controlled Selects
• Has a Master Output Control (G) for
Cascading and individual Output Controls
(GY, GW) for Each Output
• Package Option Includes 600-mil Standard
• Dependable Texas Instruments Quality and
1 OF 16 DATA SELECTORS/MULTIPLEXERS
WITH 3ĆSTATE OUTPUTS
SDAS154A − D2822, DECEMBER 1983 − REVISED JANUARY 1990
SN74AS850A, SN74AS851B . . . N PACKAGE
† CLK for ’AS850A or SC for ’AS851B
These four-line to one-line data selectors/multiplexers provide full binary decoding to select one-of-sixteen data
sources with complementary Y and W outputs. The ’AS850A has a clock-controlled select register allowing for
a symmetrical presentation of the select inputs to the decoder while the ’AS851B has an enable-controlled select
register allowing the user to select and hold one particular data line.
A buffered group of output controls (G, GY, GW) can be used to place the two outputs in either a normal logic
(high or low logic level) or a high-impedance state. In the high-impedance state, the outputs neither load nor
drive the bus lines significantly. The high-impedance third state and increased drive provide the capability to
drive the bus lines in a bus-organized system without the need for interface or pullup components.
The output controls do not affect the internal operations of the data selector/multiplexer. New data can be setup
while the outputs are in the high-impedance state.
The SN74AS850A and SN74AS851B are characterized for operation from 0°C to 70°C.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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